1. Field
The present invention relates to a ball balancer control method of a washing machine, and more particularly to a ball balancer control method capable of reducing oscillation occurring as oil viscosity in a ball balancer is changed by the temperature of washing water in a dehydration operation.
2. Description of the Related Art
In general, a balancer provided in a drum of a washing machine has a hollow ring shape in which a solid type movable member, such as balls, and oil are provided.
When laundry filled in the drum of the washing machine is eccentrically positioned and rotated in an unbalanced state, balls of the ball balancer move in a predetermined direction, due to differential centrifugal force caused by the unbalanced rotation, in order to compensate for weight deviation of the laundry eccentrically placed in the drum, thereby maintaining the balanced state.
That is, as disclosed in Korean Patent Unexamined Publication No. 1998-69776, the ball balancer has a function of reducing an oscillation of a rotation member, by using damping fluid to which an additive having predetermined viscosity of between 200 cSt and 400 cSt is added so that viscosity variation according to temperature variation is reduced.
However, the oil viscosity may vary depending on the temperature, and the oscillation is affected by the oil viscosity. Thus, the conventional method of using a fixed sensing time does not prevent the oscillation, since the sensing time is fixed when detecting unbalanced mass based on variation of the water temperature.